Development of a Toxicity Bioassay Using Fertilisation in the Green Mussel, Perna viridis, from Exposure to Copper and Cadmium

Abstract. Previous studies have shown marine bivalves to be suitable bioindicators for heavy metal pollution in the marine environment. In this study, the potential of the Green Mussel, Perna viridis to be a bioindicator of copper and cadmium contamination in the marine environment was explored. The study aimed to develop a toxicity bioassay using P. viridis, and explored if a dose-response relationship between fertilisation in P. viridis and increasing concentrations of copper and cadmium could be established. The effect of copper and cadmium on embryo formation was also examined. Few fertilisation assays involve the use of the P. viridis, a tropical marine bivalve. Rather, a temperate mussel Mytilus sp., is more commonly used. As such, this study is relevant to the Southeast Asian region. Mussel gametes were subjected to increasing concentrations of cadmium and copper over a 24h test period. Following this, the number of unfertilised eggs was counted under a microscope. Data obtained was then arcsine transformed and subjected to one way Analysis of Variance (ANOVA) and Dunnett’s test to determine if a significant dose-response curve could be established. Results indicated significant treatment effects and a degeneration of unfertilised eggs when gametes were subjected to cadmium and copper solutions.